Given that foods and nutrients have been shown to influence the pharmacokinetics of drugs, drugs may cause changes in the nutritional status of patients and their response to a given drug. Food‑drug interactions are particularly relevant for drugs used to treat neurological and psychological diseases. This review provides an overview of food‑drug interaction in the treatment of neurological and psychological diseases. A literature search was carried out by collecting data from different reviews, reports, and original articles on general or specific drug interactions with food, in patients with a variety of neurological and psychological diseases. Based on our review, we found that food‑drug interactions may alter the expected impact of drug, or cause the development of a drug toxicity. Nutritional status of the patients may also be affected, particularly a change in body weight caused by a change appetite. Metabolism, absorption, and excretion of foods may also be altered, and nutritional insufficiencies may occur. Recent studies show that diet can have a strong influence on gut microbiota and thus, alter drug pharmacokinetics. Therefore, microbiota alterations should also be considered while assessing food‑drug interactions. Knowledge of food‑drug interactions is critical for improving health of patients with neurological and psychological diseases, and also for improving effectiveness of treatments.